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V. A. Novikov

Publications and source records attributed to V. A. Novikov.

At least 19 recordsLinked to original sources

libepa -- a C++/Python library for calculations of cross sections of ultraperipheral collisions

The library provides a set of C++/Python functions for computing cross sections of ultraperipheral collisions of high energy particles under the equivalent photons approximation. Cross sections are represented through multiple integrals over the phase space. The integrals are calculated through recurrent application of algorithms for one dimensional integration. The paper contains an introduction to the theory of ultraperipheral collisions, discusses the library approach and provides a few examples of calculations.

hep-ph

Production of heavy charged particles in proton-proton ultraperipheral collisions at the Large Hadron Collider: survival factor

Ultraperipheral collisions of high energy protons are a source of approximately real photons colliding with each other. Photon fusion can result in production of yet unknown charged particles in very clean events. The cleanliness of such an event is due to the requirement that the protons survive during the collision. Finite sizes of the protons reduce the probability of such outcome compared to point-like particles. We calculate the survival factors and cross sections for the production of heavy charged particles at the Large Hadron Collider.

hep-ph

LHC as a photon-photon collider: bounds on $Γ_{X\toγγ}$

In the relatively recent CMS data, there is a hint on the existence of a resonance with the mass 28 GeV coupling to muons. Such a resonance should also couple to photons through the fermion loop, therefore it can be searched for in ultraperipheral collisions (UPC) of protons. We set an upper bound on the $X γγ$ coupling constant from the data on $μ^+ μ^-$ pair production in UPC at the LHC. Our approach can be used for similar resonances should they appear in the future.

hep-ph

Quasistable charginos in ultraperipheral proton-proton collisions at the LHC

We propose a model-independent approach for the search of charged long-lived particles produced in ultraperipheral collisions at the LHC. The main idea is to improve event reconstruction at ATLAS and CMS with the help of their forward detectors. Detection of both scattered protons in forward detectors allows complete recovery of event kinematics. Though this requirement reduces the number of events, it greatly suppresses the background, including the large background from the pile-up.

hep-ph

Dimuon resonance near 28 GeV and muon anomaly

We discuss if the resonance recently observed by CMS can be responsible for the deviation of the experimentally measured muon anomalous magnetic moment from the theoretical prediction.

hep-ph

Modification of the zirconia ceramics by different calcium phosphate coatings:comparative study

The aim of this study was to characterize different calcium phosphate coatings and evaluate in vitro cell response of these materials to ceramics implants. The physical and chemical properties of calcium phosphate coatings formed by RF-magnetron sputtering of calcium phosphate tribasic, hydroxyapatite, calcium phosphate monobasic, calcium phosphate dibasic dihydrate and calcium pyrophosphate powders were characterized. Cell adhesion and cell viability were examined on calcium phosphate coatings using mesenchymal stem cells. The results of cytotoxicity measurements of the calcium phosphate coatings revealed that only the coating obtained by RF-magnetron sputtering of the calcium phosphate dibasic dihydrate and calcium phosphate tribasic powders possessed lower cell viability than the zirconia substrate. The coating formed by sputtering of the calcium phosphate tribasic powder demonstrated more cells adhered onto its surface compared with other calcium phosphate coatings.

physics.app-ph

General properties and kinetics of spontaneous baryogenesis

General features of spontaneous baryogenesis are studied. The relation between the time derivative of the (pseudo)goldstone field and the baryonic chemical potential is revisited. It is shown that this relation essentially depends upon the representation chosen for the fermionic fields with non-zero baryonic number (quarks). The calculations of the cosmological baryon asymmetry are based on the kinetic equation generalized to the case of non-stationary background. The effects of the finite interval of the integration over time are also included into consideration. All these effects combined lead to a noticeable deviation of the magnitude of the baryon asymmetry from the canonical results.

astro-ph.CO

Modification of poly(L-lactide) and polycaprolactone bioresorbable polymeric materials by RF plasma discharge: a preliminary study evaluating EA-hy 926 cell attachment

Surface modification of poly(L-lactide) (L-PLA) and polycaprolactone (PCL) bioresorbable polymers by radio-frequency thermal glow discharge plasma is reported. Improved biocompatibility of L-PLA and PCL materials was obtained by employing hydroxyapatite target sputtering in Ar+ plasma as evidenced by the change of L-PLA and PCL properties from highly hydrophobic to hydrophilic, with absolute wettability obtained for both materials, and enhanced endothelial hybrid cell line EA-hy 926 attachment to modified surfaces. For the latter, surface properties that suppress adverse cellular responses (e.g. apoptosis, necrosis) were also attained. Surface roughness and surface free energy were found to increase significantly for both polymers under prolonged plasma exposure and, a longer chain aliphatic PCL were found to display a marginally better post plasma-treated biocompatibility compared to L-PLA.

cond-mat.mtrl-sci

A cosmological bound on $e^+ e^-$ mass difference

We demonstrate that CPT-violation due to $e^+ e^-$ mass difference generates a non-zero photon mass. As a result the cosmological bounds on the photon mass lead to the bounds on $e^+ e^-$ mass difference which are at least by 10 orders of magnitude stronger than the direct experimental bound.

hep-ph

How to see an antistar

Polarization of photons emitted in weak decays occuring at distant star allows to determine whether this star is made from antimatter. Even more promissing is the observation of neutrinos (antineutrinos) produced at neutronization (antineutronization) reactions at the beginning of SN ($\bar{SN}$) explosion.

hep-ph

Recovering partial conservation of axial current in diffractive neutrino scattering

A model of diffractive neutrino scattering is formulated in terms of the chiral hadronic current which is conserved in the limit of vanishing pion mass. This current has the correct singularity structure and, naturally, does not lead to contradictions with a partial conservation of the axial current (PCAC). In that respect we differ from earlier work in the literature, where a breakdown of PCAC had been reported. We show that such a breakdown of PCAC is an artifact of the hadronic current non-conservation in the model developed there.

hep-ph

CPT, Lorentz invariance, mass differences, and charge non-conservation

A non-local field theory which breaks discrete symmetries, including C, P, CP, and CPT, but preserves Lorentz symmetry, is presented. We demonstrate that at one-loop level the masses for particle and antiparticle remain equal due to Lorentz symmetry only. An inequality of masses implies breaking of the Lorentz invariance and non-conservation of the usually conserved charges.

hep-ph